Bearing allot



June 2, 1931- J.. v. o. PALM ETAI.- 1,807,570

' BEARING ALLDY A Filed Dec. 19.` 1928 INVENToR A TTORNEYS Patented June 2, 193,1

CMKNUTB, F CLEVELAND, OHIO, ASSGNORS TO THE CLEVELAND .GRAPHITE BRONZE COMPANY, CLEVELAND, OHIO, A CORPORATION OF OHIO BEARING annoy Application led December 19, 1928. Serial No. 327,132.

The present invention, relating, asindicated, to bearing alloys, is particularly directed to an improved metallic composition, one particular use for which is as a substitute for the ordinary Babbitt metal.

One of the principal objects of the invention is the provision of a metallic composition for the purpose indicated which shall have improved physical properties 'at high temperatures and which shall be less expensive than Babbitt metals ofordinary composition.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the followin description setting forth in detail one p rouct exemplifyingour invention, such disclosed product constituting, however, but one of vvarious applications of the principles of our invention. v

said annexed drawing The single figure there appearing is ,a sectional view showing upon an enlarged scale the appearance of our alloy in a photograph.

Our improved alloy has as a base lead in a predominant amount, with lesser amounts of other metals, such" as cadmium, zinc and antimony. `Zinc is soluble in lead only very slightly, but it alloys withcadmium and antimony in any proportions and by the use of cadmium and antimony the crystals of zinc and cadmium ,and zinc and antimony are formed which may be observed in the matrix, which constitutes the cadmium, antimony and lead.

. In the single figure appearing in the drawing the predominating black matrix is a comy bination of lead, cadmium and antimony,

while the long narrow crystals are formed orv zinc-and cadmium, and some/of zinc, cad,- mium and antimony. The smaller and more rhombic' or square crystals are cubical cr stals of cadmium and antimony and the ne grain and uniform distribution of the various crystals is very evident from the drawing. The crystal size in the grain structure can be varied by the rate of cooling, just as with ordinary babbitts.

The present alloy, which forms the subJect matter of this apphcation, constitutes a modiiication of the bearing alloy disclosed and claimed inv our Patent No. 1,745,314, dated January 28711930. Inithe alloy there disclosed, consisting of lead in predominant amount with smaller amounts of cadmium, zinc and antimony, the preferred proportions were given as approximately 67 per cent. of lead, 15 to 18 per cent. of cadmium, 5to 10 per cent. of zinc and 6 to 15 per cent. of antimony. Examination of the number of alloys consisting of the above-named ingredient/s, in

which the proportions of each have been varied through a lconsiderable range, 'discloses the fact that with the same ingredients present in different amounts than those stated vsubstantially the` same, and in some cases slightly better, qualities for certain conditions can be secured. Thus, a bearing alloy consisting of approximately 82 per cent. lead 11/2 to 71/2 per cent. zinc, 4 to 121/2 per cent. of antimony, and 4 to 91/2, per cent. of cadmium gives a hardness and duct-ility at elevated or operating temperatures which is equal or superior to the hardness and ductility of the composition -described in our patent. The lead content is of course reduced by an amount equal to the increase from the minif named for each of the other mum igures The leadgmay vary from 82 to ingredients. 7 O per cent. y

The alloy above described has approximately the same hardness as ordinary babbit-ts at low temperatures, but at elevated temperatures it is materially higher. Thus, at 250 Fahr. the relative hardness of babbitt and the present alloy may be given as 30 for babbitt and 47 for the present composition. The properties of varied somewhat while still maintaining the desirable physical characteristics. Thus, the eiiect of increasing the zinc content the antimony out of the lead and we have found that three per cent. of zinc is probably the most desirable amount to use for an alloy for general purposes.. this removal of the antimony from the lead is to make it possible to increase the zinc and antimony content without increasing the hardness of the alloy. .An increase of antimony or cadmium, or both, in the matrix,

The result of the alloy may be f is to pull accompanied by a corresponding decrease in the lead secures the desired hardness at elevated temperatures.

Certain other properties of prime importance in a bearing' metal in which our present composition is markedly superior to ordinary babbitts, are its elasticity limit, and modulus of elasticity in compression, its resistance to impact, its qualities as a bearing under restricted lubrication, and its coeH- f cient of friction. The most marked difference in these properties is found in the modulus of elasticity, which is for the vpresent composition two-thirds of that of the ordinary babbitt, and in the coefficient of friction of the two materials. Under identical conditions the friction of the present composition is Vless than two-thirds that of ordinary babbitt.

The present alloy is the only lead base babbitt which has been found satisfactory at high temperatures by virtue of better retaining its'hardnes, and this property of the alloy is due to the presence of the cadmium yand antimony in the matrix composition. The alloy may be readily mixed and formed and is materially less expensive than any of the high grade babbitts which are in general use, While its properties exceed those of all other babbitts at high temperatures.

Other modes of applying the principle of our invention may be employed instead of the one explained, change being made as regards the composition herein disclosed, provided the ingredients stated by the following claim or the equivalent of such stated ingredients be employed.

We therefore particularly point out and i distinctly claim as our invention A bearing alloy consisting of approximately 82 per cent. lead, 71/2 per cent. cadmium, 71/2 per cent. antimony, and 3 per cent. of zinc. t, Signed by us, this 17th day of December,

J OHN V. O. PALM. EDWARD C. KNUTH. 

